Solvent extraction of zirconium and hafnium from hydrochloric acid solutions using acidic organophosphorus extractants and their mixtures with TOPO

Abstract

Solvent extraction of Zr and Hf from hydrochloric acid solution was performed by using acidic organophosphorus extractants and their mixtures with TOPO. In the HCl concentration range from 1 to 4 mol/dm3, solvation reaction was responsible for the extraction of Zr and Hf by single acidic organophosphorus extractants, such as D2EHPA, PC88A and Cyanex272. Although the extraction percentage of both metals by single and mixture of extractants increased with the increase of HCl concentration, the dependence of separation factor on the HCl concentration showed opposite behavior in both extractant systems. Synergistic extraction of Zr and Hf was obtained by the mixtures. Single Cyanex272 and a mixture of Cyanex272 and TOPO were found to be the most efficient in separating the two metals. © 2013 The Japan Institute of Metals and Materials.